Clear Lake, Indiana has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 39.2 °F (low) to 58.2 °F (high). Annual precipitation averages 38 Inches. Clear Lake is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 16.4 °F | 30.9 °F | 2.45 in. |
| February | 17.6 °F | 34.2 °F | 2.13 in. |
| March | 25.7 °F | 44.9 °F | 2.45 in. |
| April | 36.7 °F | 58.0 °F | 3.54 in. |
| May | 48.6 °F | 69.5 °F | 4.19 in. |
| June | 58.2 °F | 78.8 °F | 3.89 in. |
| July | 61.2 °F | 82.3 °F | 3.74 in. |
| August | 59.3 °F | 80.3 °F | 3.94 in. |
| September | 51.8 °F | 74.3 °F | 3.25 in. |
| October | 41.0 °F | 61.5 °F | 3.04 in. |
| November | 31.0 °F | 47.6 °F | 2.97 in. |
| December | 22.5 °F | 35.7 °F | 2.39 in. |
| Annual | 39.2 °F | 58.2 °F | 37.98 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |